I'd like to get rid of some kernel features that i don't need/not necessary but yet there's no options for getting them disabled upon looking inside the NOTES configuration file (I'm thinking about jailing for instance but there might be others)
I'm aware of WITHOUT_JAIL entry in src.conf but it only affects user-land program tools.
Thank you in advance for answers
I think it should like linux kernel configuration that such likes tool: Menuconfig.
I don't really mind about the way that the kernel is configurated, just i'd like to let one all kernel features that can be optional to be so (in fact there's many that are so yet somes aren't like i've stated in my initial post)
This bug report is too vague to be actionable. There is a maintenance cost in having kernel components be optional, and sometimes it simply doesn't make sense to do so when the component is tightly coupled with the rest of the kernel. Jails are an example of this, and you didn't list any others.
Please post to a mailing list (-questions or -hackers perhaps) and clearly state what it is you're trying to achieve. It may be possible to do what you want without modifying the kernel.